Healthcare providers in all 50 states are required by law to report new cases of cancer to their state?s cancer registries. The National Cancer Institute?s (NCI?s) Surveillance, Epidemiology, and End Results (SEER) Program, collects data on each and every cancer patient in SEER covered areas. This data includes demographics, a description of their cancer, limited initial treatment information, and patient follow-up including cause of death for deceased patients. In the past the main source of registry data came from Hospitals. With the increasing complexity of cancer care and delivery systems, patients are being increasingly treated exclusively at physicians? offices. Thus, for SEER to continue capturing all cancer cases and their treatment information SEER is interested in obtaining other sources of data such as claims data from oncology practices. Oncology practice claims has proven to be a rich source of information on detailed systemic therapy, including agents, doses administration dates etc.